1. Field of the Invention
This present invention relates to an electromagnetic induction device, and more particularly, to an electromagnetic induction pen-like device with writing function.
2. Description of the Prior Art
Currently, the most widely used computer input devices include the keyboard and mouse. Due to the advancement of digital technologies, more and more computer users are starting to work with digitizer-based devices such as a digitizer tablet, which allow a user to write and draw upon the working area of the tablet and have the signals and codes interpreted by a computer. Specifically, the working area of the tablet provides a writing surface for capturing the position, pressure and the key status of an object, such as a pen or a mouse, and the information from pressure and actuated keys etc. In cooperation with the tablet, a pen-like device is required to create such objects.
One pen-like device is disclosed in U.S. Pat. No. 4,697,050, as shown in FIG. 1. The pen-like device comprises a writing device 110 and an erasing device 120. The writing device 110 and the erasing device 120 can be employed for inputting and correcting on a tablet. The above-mentioned pen-like device further comprises a battery 130 therein. The battery has to be charged or changed periodically. The problem such as the breakdown or aging of the battery becomes a pain in the neck for the user. In order to charge the battery, there is a metal contact 135 on the shell of the pen-like device. The metal contact 135 may induce the dangers of electrical leakage to the user. Moreover, an oscillator circuit 140 and a charge circuit 145 are employed in the above-mentioned pen-like device. The above-mentioned circuit design will increase the complexity, the chance for breakdown and the cost of the pen-like device. Furthermore, sometimes the oscillator circuit 140 may cause large inaccuracies in the pen-like device.
Referred to FIG. 1B, another pen-like device is disclosed in U.S. Pat. No. 5,576,502. The above-mentioned pen-like device comprises a writing portion 150 at one side of the pen-like device, and a rubber portion 160 at the other side of the pen-like device. The rubber portion 160 is employed for handwriting trace correction of the writing portion 150 on a tablet. However, in the above-mentioned pen-like device, in order to add the correction function, the addition of large members and circuits will increase the complexity and cost of the pen-like device.
Hence, it is an important object of this invention to provide a pen-like device without the defects in the prior art. Additionally, it is also an important object of this invention to provide an electromagnetic pen-like device with multiple functions.